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Max Lin

Can the user-seen pair setup that does not suffer from missing data problem be treated as a special case of the user-rateing pair, but with seen movies with rating 1 and unseen movies with with rating 0?


Max: In terms of running the algorithm, you can do as you said. What you'll notice is that the matrix is now complete as opposed to very sparse in the case of ratings.


But doesn't the user-seen pair also suffer from not distinguishing between user - 'not aware movie existed' and user - 'chose not to watch it'


Chris: Awareness is a different concept. The proposed model is based on actual watching; aware but don't watch is grouped with not aware. You can of course build a more complicated model if you so desire.

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